"The question is, does anyone in the Parliament have the political will to stand up to the mining companies, especially in an election year?

"The Greens have the courage to do that. We're prepared to work with Labor.

"We'll pass it any time between now and winter break. We saw that this was a problem.

"Now that the whole country can see it's a problem, it really is incumbent on the Government to work with us to fix it."

The Opposition's Mathias Cormann says the Coalition will support an inquiry into the design of the mining tax.

"We do think it should be scrapped and any inquiry into the mining tax won't change our position in relation to this," shadow assistant treasurer Mathias Cormann said.

"However if the Greens want to give another platform to critics of the mining tax to come out and explain why the mining tax is a bad tax which came out of a bad process, good luck to them. We won't stand in their way."

Treasurer Wayne Swan says he has nothing to fear, and the tax should not be judged after just six months.

"It just so happens and it's politically inconvenient that in the second half of last year commodity prices crashed and that had an impact on revenues," he said.

"That occurred more generally but these are just facts of life that responsible economic managers take into account."